Table 3. Correlative factors of well-developed collaterals defined by Werner’s CC grading.

Variables	Odds ratio (95% CI)	P-value
CC: collateral circulation.
Diabetes mellitus	1.159 (0.950–1.414)	0.15
Occlusion myocardial infarction	1.408 (1.140–1.739)	0.002
Current smoker	0.803 (0.668–0.996)	0.02
Left ventricular ejection fraction	1.012 (0.998–1.025)	0.09
Reference vessel diameter	2.139 (1.728–2.647)	< 0.001
Chronic total occlusion length	1.001 (0.993–1.008)	0.85
Moderate or severe tortuosity	0.932 (0.760–1.142)	0.50
Target vessel
Left anterior descending	0.577 (0.058–5.759)	0.64
Left circumflex artery	0.935 (0.092–9.509)	0.94
Right coronary artery	0.414 (0.041–4.144)	0.41